Calculator.



Patented Dec. 30, I902.

' T. FHEGOSO.

GALGU LATOR.

(Application filed July 25 1902.)

(No Model.)

v) R 2 R q '2 3 an An ELFLILLlFLLIFLL INVENTOH' A no WITNESSES:

DNITED' STATES PATENT OFFICE.

TOMKSFREGOSO, OF HERMOSILLO, MEXICO.

CALCU LATO R.

SPECIFICATION forming part of Letters Patent No. 717,381, dated December30, 19 02.

I Application filed July 25, 1902. Serial'No. 116,942. (No model.)

The object of the invention is to provide a new and improved measuringinstrument, more especially designed for surveyors and other persons andarranged to permit of readily and accurately finding without calcu-.

lation rectangular oodrdiuates to any dis tances with any angle in thesexagesimal or centesimal system, to solve right-angle triangles andoblique-angle triangles by giving immediately and accurately threerequired or unknown measurements, and when the other three measurementsare known to reduce stadia distances to the horizon and to find thediiference of elevation between any two points.

The invention consists of novel features and parts and combinations ofthe same, as will be fully described hereinafter and then pointed out inthe claims.

A practical embodiment of the invention is represented in theaccompanying drawings, forming a part of this specification, in whichsimilar characters of reference indicate corresponding parts in bothviews.

Figure l is a face view of the improvement, and Fi 2 is an enlargedtransverse section of the same on the line 2 2 of Fig. l.

The rectangular frame A is provided on opposite sides with parallellengthwise-extending graduations B B, representing millimeters andsubdivisions, and on the said frame is secured a quadrant 0, havinggraduations C and C of which the outside graduation O is dividedsexagesimally and the innor graduation C is dividcd contesinially. Therule D for the quadrant O is provided with a graduation ID inmillimeters and subdivisions thereof, and on the said rule are ar rangedverniers E E for the graduations G 0 and on the said rule is slid-ablyheld a vernier F for reading one-twentieth of a millimeter on thegraduation D. A set-screw F on the vernier Fserves to fasten the same onthe rule D, and a set-screw D serves to fus ten the rule D o 1 thequadrant C. A semicircular protra tor G is mounted to slide lengthwiseon suitable guideways arranged on the frame A, and the said protractorGis provided with graduations G G similar to the graduations G C and onthe protractor indicates a scale-bar H, having a graduation H ofmillimeters, and on the said scale-bar are arranged verniers I I forreading fractions on the protractor gradnations G G respectively. Avernier J is slidable on the scale-bar Hand is arranged for readingonetwentieth of a millimeter on the scale-bar graduation H. A set-screwH serves to fasten the scale-bar H in position on the protractor G. Thelatter is adapted to he moved lengthwise of the frame A by arack-andpinion movement K, as will be readily understood by reference toFig. 2. The starting-point of distances or sides given to solvetriangles is at zero of the graduation B. The starting-point in thequadrant O is given at zero of the graduations O 0 and the starting-point of. the protractor G is at the left given at zero on bothgraduations G G The starting-points of the rule D and scale-bar H are attheir pivots.

The instrument is used as follows: To find 8b rectangular coordinates,the operator sets the rule D firmly at a given angle, the vernier F isfixed at a given distance, and the scale-bar H is fixed at right anglesto the graduation Bthat is, at ninety degrees on the graduation G'andthen the protractor G, with the scale-bar H, is moved lengthwise on theframe Aalong the graduation B until the zero of the vernier J touchesthe zero of the vernier F. The distance of the gradual-5 tion B nowgives the ordinate or latitude and. the distance on the graduation H ofthe scale-bar H indicates the departure or abscissa to the givendistance and hearing. The reciprocal problemthat is, coordinates beinggiven, to find the distance and angleis easily solved by setting thelatitude on the graduation B and the departure on the scalebar II atright angles to each other. The rule D is now swung until the zero ofits vei-nier F touches the zero of the vernier J, which marks thedeparture, and hence the problem is solved, because the angle sought foris marked 'on the quadrant by; the verniers E E and the distance isindicated by the linear vernier in order to solve an oblique-angletriangle, the operator proceeds as follows: The scalebar H is set atright angles to the graduation B and fastened in place on the protractorG by the set-screw H and then the protractor and scale-bar are movedalong the guide Way on the frame A until the distance of the side knownis reached on the graduation B. The protractor G is now fixed in placeand the scale-bar H is swung on the protractor G to indicate one of thegiven angles. By similar means the other given angle is sought on thequadrant C by the rule D and then the intersecting point of the rule Dand scalebar H indicates the length of the other two sides, readingbythe verniers F and J. The triangle is thus mechanically solved in allits sir; elements-namely, three sides and three anglesand Without anycalculation or danger of making mistakes. The examples above given onlydemonstrate the use of my instrument in plain trigonometry When the datais one side and two angles; but other cases may be accurately solvedWith the same ease and speed. The data can be set on the instrument atthe time such. data are obtained in the field; but it is evident thatthe instrument can be used as a planetabl'e, having the telescope overthe rule D.

From the foregoing it will be seen that the instrument givesthe value ofall the natural trigonometrical lines, and when solving a triangle itgives not only one side or one an gle, but indicatesat once all theunknown quantities sought for, and at the same time the instru mentforms the triangle to be solved, thus giving a graphical approval to thedata and operation, if both have been logical; but in case they are notcorrect the instrument does not make a triangle, hence indicatingthatthe data are Wron It Will further be seenthat all that is necessaryto do to use the instrument is to maize three lineal and two angleVernier readings and no other calculations except the simple one of theproportional scale or value given to the'graduations on the rules,according to the magnitude of the side known, being in direct proportionto the extension of the same, the denominator of the ratio, orrelationship used.

Having thus described my invention, 1 claim as new and desire to secureby Letters Patent- 1. A measuring instrument of the class described,coinprisiug a frame having parallel winner lineal graduations, aquadrant fixed on the frame and having a double degree graduation and apivotal rule having a linear graduation, a vernier on the said rule forreading fractions on the linear graduation of the rule, verniers on therule for reading fractions of degrees on the double degree graduation, aprotractor having double degree graduations, and adjustable on the frameto and from the quadrant, a pivoted scale-bar for the protractor andhaving linear graduations, a ver nier slidahle on the scale-bar forreading fractions of the linear graduation thereon, and verniers on thescale-bar for reading fractions on the said protractor graduations, asset forth.

2. -A measuring instrument of the class described, comprising arectangular frame having lineal scales on opposite sides, a quadrantfixed on the frame, a pivoted rule movable angularly on the quadrant,and having a lineal scale, means for adjust-ably securing the rule tothe quadrant, a protractor, movable longitudinally on the frame, apivoted scale-bar, movable angularly on the protractor andlongitudinally on the frame therewith, said scale-bar and said rulebeing disposed to lie in mutually-intersecting planes and each movableangular-1y in either direction on and independently of the other, andsaid protractor having means, coacting with the lineal scale on theframe, to indicate the distance between the pivoted portions of the ruleand scale-bar and means for adj'ustably securing the scale-bar to theprotractor, substantially as described.

3. A measuring instrument of the class dese *ibed, comprising arectangular frame having lineal scales on opposite sides, a quadrantfixedly secured to the frame and having two graduationma rule pivoted tothe quadrant and adjustably secured thereto, said rule being providedwith two fixed verniers and an adjustable Vernier, a protraotor slidablymounted on the frame and provided with two gradnations, and a scale barpivoted to the protractor and adjustahly secured thereto, said scale-barbeing provided with two fixed verniers and an adjustable vernier, as setforth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses. I

TQMAS FREGOSO. W'itnesses:

DAVIS RICHARDSON, FRANK M. GsooKER.

ICO

